Please don’t make this a rim vs disc bloodfest. Stage 17 won with rim brake

Discuss light weight issues concerning road bikes & parts.

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tomato
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by tomato

Lina wrote:
Wed Jul 28, 2021 9:03 pm
iheartbianchi wrote:
Wed Jul 28, 2021 5:01 pm

You don't understand racing. Braking in a race is a VERY niche application. Do you know how much time we spent training our elite cyclists how to brake on downhills? Zero. Actually I don't even know how we would design a braking training session. Go really fast and brake until you lock up and fall over? That reminds me - we did do drills where we intentionally locked up the rear wheel to get our riders comfortable with rear wheel slip, but we would never even consider asking them to lock up their front wheel intentionally. Also, if you're concerned about braking in a downhill in a racing sitaution, you are doing something terribly wrong. Going downhill is all about going down as fast as you can, and the biggest part of this is good line (which means recon recon recon and memorizing each turn before the race), precise weight distribution, micro shifts in center of gravity during a turn, and minimal application of brake possible.
Why would you ever intentionally lock up a front wheel? And how bad are you as a coach if you can't come up with a drill for braking?
My former coach had us do descending/braking drills, since the key to a fast technical descent is picking the right line and braking at the right time. But, the drills did not involve locking up a wheel and falling over!

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Nickldn
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by Nickldn

tomato wrote:
Wed Jul 28, 2021 9:38 pm
Lina wrote:
Wed Jul 28, 2021 9:03 pm
iheartbianchi wrote:
Wed Jul 28, 2021 5:01 pm

You don't understand racing. Braking in a race is a VERY niche application. Do you know how much time we spent training our elite cyclists how to brake on downhills? Zero. Actually I don't even know how we would design a braking training session. Go really fast and brake until you lock up and fall over? That reminds me - we did do drills where we intentionally locked up the rear wheel to get our riders comfortable with rear wheel slip, but we would never even consider asking them to lock up their front wheel intentionally. Also, if you're concerned about braking in a downhill in a racing sitaution, you are doing something terribly wrong. Going downhill is all about going down as fast as you can, and the biggest part of this is good line (which means recon recon recon and memorizing each turn before the race), precise weight distribution, micro shifts in center of gravity during a turn, and minimal application of brake possible.
Why would you ever intentionally lock up a front wheel? And how bad are you as a coach if you can't come up with a drill for braking?
My former coach had us do descending/braking drills, since the key to a fast technical descent is picking the right line and braking at the right time. But, the drills did not involve locking up a wheel and falling over!
I think the point is to get used to locking up and NOT falling over. It's a good skill to learn being somewhat comfortable when things go to shit.
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warthog101
Posts: 167
Joined: Wed Sep 25, 2013 10:05 am

by warthog101

Alexbn921 wrote:My list of importance:
Comfort
Handling
Braking
aero
weight
I like light bikes, disk brakes and don't care what the anyone else rides. Get out and put in miles.
As this is the topic to argue about nonsense, aero is above braking and handling I reckon. Image
Any braking system by the major players works well enough imo.

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wheelsONfire
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by wheelsONfire

tomato wrote:
Wed Jul 28, 2021 8:09 pm
wheelsONfire wrote:
Wed Jul 28, 2021 7:51 pm
I bet 99% of people who hated disc brakes 10 years ago sit and argue how good they are now.
Who hated road disc brakes 10 years ago? They were effectively non existent at that point in time.
No, you are wrong!
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Mr.Gib
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by Mr.Gib

As hilarious as some of you maniacs are, if I can just respond to the OP, from what I can tell, it always seems to be about weight with the pros regardless of what the data tells us about the value of aero. Apparently a couple of the ISN riders did ride rim brakes at the Tour de France. They were on O2 VAMs painted like Ostros (flicker pattern). How did the rim brake crowd miss this. There was even a discussion about Sylvan Adams saying that Froome could ride rim brakes if he wanted. Well, apparently he did. How did a photo of this not appear? Apparently the reason was to go as light as possible. And that's coming from an Ostro which must be one of the lighter disc bikes out there. Is someone now going to yell "race war"? :D
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

BigBoyND
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by BigBoyND

I find some of the arguments against rim brakes odd.

How often do people wear out carbon brake surfaces on road bikes? I've never seen such a thing happen in practice.

The argument for wheen clearance is just as odd. Rim brakes are limited to ~28mm because they were designed/sized for those. The design can scale. Shimano could very easily make a bigger caliper if they wanted to fit 32mm tires.
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Tifosiphil
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by Tifosiphil

BigBoyND wrote:
Thu Jul 29, 2021 9:32 am
I find some of the arguments against rim brakes odd.

How often do people wear out carbon brake surfaces on road bikes? I've never seen such a thing happen in practice.

The argument for wheen clearance is just as odd. Rim brakes are limited to ~28mm because they were designed/sized for those. The design can scale. Shimano could very easily make a bigger caliper if they wanted to fit 32mm tires.
I normally get through an alu wheelset in around 2 years in all weather 8-10,000km. My carbon wheelset lasted about 12,000km but I couldn't ride them through winter due to the abysmal breaking

usr
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by usr

BigBoyND wrote:
Thu Jul 29, 2021 9:32 am
How often do people wear out carbon brake surfaces on road bikes? I've never seen such a thing happen in practice.
How much of that is because we tend to sacrifice our aluminium wheels in wet conditions?
The argument for wheen clearance is just as odd. Rim brakes are limited to ~28mm because they were designed/sized for those. The design can scale.
No it can't: increasing the size inevitably increases flex and then you get a terrible brake (or a not quite terrible but still not good brake that is absurdly heavy). Disc brakes perform well enough that they can get by with the bad leverage resulting from the tiny disc radius (compared to rim) mainly because their calipers go around the disc so tightly.

Oh no, I'm starting to sound like a pro-disc person 😱
Last edited by usr on Thu Jul 29, 2021 1:54 pm, edited 1 time in total.

Mcdeez
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by Mcdeez

Its so funny to read all of these comments and so many silly arguments lol

blutto
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by blutto

usr wrote:
Thu Jul 29, 2021 11:47 am
BigBoyND wrote:
Thu Jul 29, 2021 9:32 am
How often do people wear out carbon brake surfaces on road bikes? I've never seen such a thing happen in practice.
How much of that is because we tend to sacrifice our aluminium wheels in wet conditions?
The argument for wheen clearance is just as odd. Rim brakes are limited to ~28mm because they were designed/sized for those. The design can scale.
No it can't: increasing the size inevitably increases flex and then you get a terrible brake (or a not quite terrible but still not good brake that is absurdly heavy). Disc brakes perform well enough that they can get by with the bad leverage resulting from the tiny disc radius (compared to rim) mainly because their calipers go around the disc so tightly.

Oh no, I'm starting to sound like a pro-disc person 😱
Nahhhh.....back in the day Campy Record brakes came in two sizes ( the "old school" size could accommodate the larger tires typically used by "cyclo-tourists" ....and the "new school" race specific brakes were shorter with clearances not unlike their current cousins..).....had and used both extensively....weight increase was negligable and braking performance was not noticeably different.

So if history is a good guide would seem it be fairly simple to produce efficient light-weight rim brakes to accommodate larger tires ( and any weight difference would be insignicant compared to the added weight boat anchors, errrr, discs bring to the table...) With the added advantage that the front end could be optimized solely for steering ( no need for reducing the fork's compliance away from that optimally required for proper/best handling..., and there would be no added un-sprung weight at the end of a long lever in a very critical part of a frame's ability to handle in critical conditions (....unless of course if you prefer the laser-like handling of a MTB these are moot points...and the road bike version is actually not quite as utterly awful as some people make it out to be..).

iheartbianchi
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by iheartbianchi

Lina wrote:
Wed Jul 28, 2021 9:03 pm

Why would you ever intentionally lock up a front wheel? And how bad are you as a coach if you can't come up with a drill for braking?
I said we would never consider intentionally locking up a front wheel. The locking up of the rear wheel drill we always did on flats at reasonably safe speeds (I think we only did this once or twice since racers lock up their wheels plenty during training/racing and it's not really something they need specific training on). We don't do downhill braking drills. We do downhill training, but there the focus is all about reading corners, picking the right line and modulating speed, and shifting your body weight. Usually this means you have a good descender leading the way at gradually increasing speeds and the newbies following and learning by trial and error. Usually the feedback is "let go of your brake" or "trust the line" or "get your COM more centered over the bike." I've never had to tell a racer "brake more" or "brake harder." Quite the opposite. "Stop braking!!!!" is what we used to scream out of our car. Not that they needed much encouragement. Most of these 14-16 year olds have no fear and come to us having already learned how to descend at very fast speeds on their own.

We never had a tutotorial on how hard you should be squeezing the brakes or when you should start braking, because this is all subjective and depends on your brake setup, road conditions. This stuff comes natural to athletes who are riding 20,000km per year and have gone down countless descents in training and in races. Not much to train there. It's not like motorsports where you pick a specific braking point on a circuit that has 25 specific corners and yo're trying to squeeze out 1/10 of a second in each corner. In a road race you're looking at hundreds of corners, and the focus is on holding wheels, conserving energy and timing attacks. Braking is such a tiny part of bike racing it's insane to even be talking about which brake system is better for racing.

But again, all this is really only relevant for bike racers. This has nothing to do with recreational cyclists. Is a $20,000 carbon bike objectively better than a $3,000 carbon bike? No. It is subjectively better if you're a racer. Is a 53-39 and 11-25 objective better? It's faster for racers, but subjectively for amateurs it's not good. (Which begs the question - why aren't we all trying to emulate the racers' choice of gearing which makes you go faster, but we obsess over their choice of brake, which is something that makes you go slower and backwards? Odd.)

What's the point of a guy getting a stiff racing bike with "racer look" if you're going to set it up like an MTB, with no drop and 20mm spacers, using granny gearings (how many pros are riding compacts with 12-34 in the back) other than "trying to look pro." What's the point of wearing expensive, uncomfortable aerofit jerseys/bibs just to look pro, if you're not racing. Do you need a $400 helmet or $500 shoes because they are "objectively" better for a pro cyclist? Is a Ferrari objectively better if you're looking for an economical daily driver? Are disc brakes objectively better if you're not racing down alps? Again, who cares what the pros do or use. It's all marketing hype of technologies that are irrelevant to almost every other cyclist out there. Save your money, save your passion, and just go out there and ride. If you've got the money and spending money makes you happy, then yes you can follow what the pros do and try to emulate them all you want. But you should probably try to emulate their training and diet first, because no amount of money is going to make an out of shape, slow rider look pro. But if you can hammer out climbs at 6-7W/Kg, now we're talking and maybe then let's start obsessing over which tech can make you a tiny bit faster. Otherwise it's just appearances.
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Lina
Posts: 211
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by Lina

iheartbianchi wrote:
Fri Jul 30, 2021 5:28 am
Lina wrote:
Wed Jul 28, 2021 9:03 pm

Why would you ever intentionally lock up a front wheel? And how bad are you as a coach if you can't come up with a drill for braking?
I said we would never consider intentionally locking up a front wheel. The locking up of the rear wheel drill we always did on flats at reasonably safe speeds (I think we only did this once or twice since racers lock up their wheels plenty during training/racing and it's not really something they need specific training on). We don't do downhill braking drills. We do downhill training, but there the focus is all about reading corners, picking the right line and modulating speed, and shifting your body weight. Usually this means you have a good descender leading the way at gradually increasing speeds and the newbies following and learning by trial and error. Usually the feedback is "let go of your brake" or "trust the line" or "get your COM more centered over the bike." I've never had to tell a racer "brake more" or "brake harder." Quite the opposite. "Stop braking!!!!" is what we used to scream out of our car. Not that they needed much encouragement. Most of these 14-16 year olds have no fear and come to us having already learned how to descend at very fast speeds on their own.

We never had a tutotorial on how hard you should be squeezing the brakes or when you should start braking, because this is all subjective and depends on your brake setup, road conditions. This stuff comes natural to athletes who are riding 20,000km per year and have gone down countless descents in training and in races. Not much to train there. It's not like motorsports where you pick a specific braking point on a circuit that has 25 specific corners and yo're trying to squeeze out 1/10 of a second in each corner. In a road race you're looking at hundreds of corners, and the focus is on holding wheels, conserving energy and timing attacks. Braking is such a tiny part of bike racing it's insane to even be talking about which brake system is better for racing.

But again, all this is really only relevant for bike racers. This has nothing to do with recreational cyclists. Is a $20,000 carbon bike objectively better than a $3,000 carbon bike? No. It is subjectively better if you're a racer. Is a 53-39 and 11-25 objective better? It's faster for racers, but subjectively for amateurs it's not good. (Which begs the question - why aren't we all trying to emulate the racers' choice of gearing which makes you go faster, but we obsess over their choice of brake, which is something that makes you go slower and backwards? Odd.)

What's the point of a guy getting a stiff racing bike with "racer look" if you're going to set it up like an MTB, with no drop and 20mm spacers, using granny gearings (how many pros are riding compacts with 12-34 in the back) other than "trying to look pro." What's the point of wearing expensive, uncomfortable aerofit jerseys/bibs just to look pro, if you're not racing. Do you need a $400 helmet or $500 shoes because they are "objectively" better for a pro cyclist? Is a Ferrari objectively better if you're looking for an economical daily driver? Are disc brakes objectively better if you're not racing down alps? Again, who cares what the pros do or use. It's all marketing hype of technologies that are irrelevant to almost every other cyclist out there. Save your money, save your passion, and just go out there and ride. If you've got the money and spending money makes you happy, then yes you can follow what the pros do and try to emulate them all you want. But you should probably try to emulate their training and diet first, because no amount of money is going to make an out of shape, slow rider look pro. But if you can hammer out climbs at 6-7W/Kg, now we're talking and maybe then let's start obsessing over which tech can make you a tiny bit faster. Otherwise it's just appearances.
Have you ever watched racing of any level that involves downhills? Descending and braking doesn't come naturally to nearly everyone. The people who you scream to stopp braking are those for whom descending doesn't come naturally. You screaming to them to stop braking doesn't help at all. Going over braking and training it might just help them, instead of just screaming to them that they need to stop braking when they obviously don't know what to do. While picking the right line and have speed are important so is braking when it comes to downhills. And braking hard is important, you want to brake hard for a short time to optimize your average speed. You can't do that unless you've trained hard braking.

53-39 and 11-25 isn't even better for a racer unless it's a flat race. And you do see plenty of pros even with 34s and some with even smaller chainrings on the days that have steep climbs. It's not 2005 anymore, not even the pros are riding corncobs everywhere.

$500 shoes can be much better than some other shoes. Or then $150 pair of shoes fit your feet better. Same with helmets. That's down to personal fit and you should get the ones that FIT you. Not something based on price or what a certain pro uses. And aero jerseys are certainly not uncomfortable. In fact I refuse to ride anything but aero jerseys because they're simply much more comfier than anything else as there's absolutely no flapping in the wind.

And I'm doing extended climbs at over 5.5 W/kg, so this stuff does matter to me.

Everything you say makes you sound like every other coach that's stuck in the 90s.

tomato
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by tomato

iheartbianchi wrote:
Fri Jul 30, 2021 5:28 am
We don't do downhill braking drills. We do downhill training, but there the focus is all about reading corners, picking the right line and modulating speed, and shifting your body weight.
How do you modulate speed on a descent?

iheartbianchi
Posts: 680
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by iheartbianchi

tomato wrote:
Fri Jul 30, 2021 7:56 am
iheartbianchi wrote:
Fri Jul 30, 2021 5:28 am
We don't do downhill braking drills. We do downhill training, but there the focus is all about reading corners, picking the right line and modulating speed, and shifting your body weight.
How do you modulate speed on a descent?
A combination of position, line, pedaling and braking? Stuff that happens holistically and not at a static designated "braking zone."

Your question implies that modulation of speed only happens when you need to go slower., ie not a racing mentality. The modulation of speed also works to figure how to go faster.
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usr
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by usr

Safe/ish fast descending on the open road is all about avoiding mistakes when dealing with the unexpected. We have a multidimensional envelope of hard limits defined by tire grip (lateral and w.r.t braking) and soft limits defined by various aspects of body control, e.g. our ability to deal with bumpyness, to deal with bumpyness while braking, impose temporary line shifts and so on. Keeping some body control reserves for the unexpected is what usually limits our braking, not "whatever the tires and the calipers can give", like it surely is when you are strapped in a race car weighing twenty times your body weight. We are our own suspension systems, despite all seatpost comfort metrics, in many crashes caught on film the first sign of the envelope getting left behind is not a lateral sweep or a straight tipover, it's the rear getting all jumpy, as if it was a rodeo.

If we max out those envelopes, like one would do in a racing video game (and in certain motorsports disciplines I suppose) we'd be very, very fast but wouldn't make it to the third hill. A good descender is the one who'll pick an emergency line inside this envelope when meeting the unexpected, a bad descender will overreact. A "maxer" wouldn't have any other line available. There are many fast, bad descenders (not as fast as the hypothetical maxer). Some eventually become good, others are fast until they start to obey rule#64.

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